Ultracapacitors overcome hybrid shortcomings

For a nation that loves power, electric cars have as of yet disappointed. They’re great for puttering around town, but if you want a little kick in your ride, you’re just not going to find it in an electric vehicle without paying the price tag for enormous battery packs (e.g. Tesla). And those battery packs come both with large environmental impacts and problems for automotive manufacturers who are nervous about warranty issues.

A new company AFS Trinity claims to have a solution that will transform the plug-in hybrid drive train...the ultracapacitor. I recently spoke with CEO Joel Leventhal about their new technology called XH-150, and he explained the innovative “hyrbid within a hybrid” system.

In a regular hybrid, like a Prius, the engine kicks on and off to make up for the lack of power in the battery. This is hard on the battery pack and ends up using a lot of gasoline, hence the Prius’ somewhat unimpressive 40 MPG. The scientists at Trinity solve the problem by adding a bank of ultracapacitors for fast energy transfer.

What’s an ultracapacitor? Capacitors are passive electrical components that store energy in the field between two plates. Unlike batteries, which are designed to give a steady amount of energy over a long period of time, ultracapacitors do just the opposite, providing powerful bursts of energy in a short period of time. They also have no moving parts, are easy to maintain and have a long life span.

So the AFS system piggy backs on a typical hybrid drive train, drawing steady power from a now much smaller battery pack and charging up the ultracapacitors for the bursts of energy a typical driver needs. A control mechanism will regenerate energy on braking, and decide when to charge the ultracapacitors.

A single charge (which takes about 4 hours) can get you 40 miles without using a drop of gas and while maintaining the performance associated with a regular gasline vehicle. The typical American commute is about 32 miles, so for most of us, the gas tank would stay half-full all the time. For longer trips, you have the option to gassing up.

Trinity AFS caused quite a stir at last month's LA Auto Show when they refused to remove their dramatic 150 MPG gallon claim when asked to do so by auto show officials. They left the show and moved across the street where they were test-driving a retrofitted Saturn Vue. In a certain sense, the claim is erroneous. Theoretically, the car doesn't even require gasoline, so an MPG rating is not quite applicable. But in practice, Trinity's estimate is probably about right -- a single 80-mile trip (which would require gas for 40 miles out of approximately 300 total for a week) would require 2 gallons of gasoline, yielding the 150 MPG figure.